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Re: PATCH: reorg branch displacement fix


In message <Pine.LNX.4.21.0210311508160.3016-100000@mail.kloo.net>, tm writes:
 >
 >This fixes the problem mentioned in:
 >
 >http://gcc.gnu.org/ml/gcc-bugs/2002-06/msg00896.html
 >
 >When a conditional branch jumps to an unconditional branch, reorg will
 >thread the branch without checking if the conditional branch has enough
 >displacement bits to branch to the target.
 >
 >This patch uses MD_CAN_REDIRECT_BRANCH (as suggested by Joern in followup
 >messages to original message) to implement the substitution checking.
 >
 >Please review and if correct, commit as I don't have CVS access.
 >
 >Toshi
 >
 >Thu Oct 31  Toshiyasu Morita  <toshiyasu.morita@hsa.hitachi.com>
 >
 >	* reorg.c (relax_delay_slots): Don't thread conditional jump
 >        through unconditional jump if the conditional jump can't reach
 >        the branch target on this processor target.
This is wrong.  reorg does not and should not be checking branch displacements.
That is a problem for shorten-branches and the backend.

jeff


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